Recommended Posts

I am planning to use a CMB24D this year for my cristhmas show. However I am wondering what is the maximal wire length between the board and the RGB Floods ? I am seeing that my controller will be pretty far from the RGBs? I am planning to have them 35 feet away? Could i have any issues with the signal or current?

Thanks in advance for your help

S.

Share this post

Link to post

Share on other sites

I am planning to use a CMB24D this year for my cristhmas show. However I am wondering what is the maximal wire length between the board and the RGB Floods ? I am seeing that my controller will be pretty far from the RGBs? I am planning to have them 35 feet away? Could i have any issues with the signal or current?

Thanks in advance for your help

S.

I use 18g wire and I have a run that is 75' and has no problems. Thicker wire will be better rather then the 20g and 22g wire.

Share this post

Link to post

Share on other sites

Thanks again, by any chance do you know where i can see the board specification for a case scenario where all of them are far away? I am having some challages to place the controller close of the rgb floods.. At this point, I am planning(I need) to have a command center(all controller ) in the back yard powering the light in the front-end of my house..

Share on other sites

But please make those long runs an exception instead of the rule. I don't know how many long runs like that can be made on the same controller, it may be too much if you have four or five of them.

Shouldn't make any difference. All the controller would care about is current draw per channel and a longer cable would not affect that. I also have a bunch of 50 - 70 foot runs (along with some shorter ones). The only real limitation is voltage drop to the lights. That depends on the resistance of the wire and the current draw. In memory of Ohm's law, voltage drop for the wire is the current in amps times the resistance in ohms. So a 5 meter dumb RGB strip which will draw about three amps per color. At full brilliance using 18 AWG copper wire, would drop about 1.9 volts in each color wire on a 100 foot run. The common wire (because it has more current - assuming a single wire for the common positive voltage) would drop about 5.7 volts. That means that if you started with 12.0 volts at the controller, the lights would only see 4.4 volts. Obviously that would not work well! In reality it would not be that low because the lights would not draw as much current at that low of voltage (depends on the lights), which would result in the current being less, and therefore the voltage drop being less, but you get the idea. With 16 AWG wire, the voltage drop would be a little over half that and with 14 AWG wire it would be just over a third. Depending on what I'm doing, I have lights on everything from 18 to 12 AWG wire with most of my stuff using 16 AWG.

There are MANY sources of resistance of wire sizes on the net, but this one was the first one in a Google search: